It is the contention of many scientists that the health and well being of people can be positively or negatively influenced by the microorganisms which inhabit the gastrointestinal tract, and in particular, the large bowel. These microorganisms, through the production of toxins, metabolic byproducts, short chain fatty acids and the like affect the physiological condition and health of the host.
The constitution and quantity of the gut microflora can be influenced by conditions or stress induced by disease, life style, travel, and other factors. If microorganisms which positively affect the health and well being of the individual can be encouraged to populate the large bowel, this should improve the physiological well being of that individual.
The introduction of beneficial microorganisms, or probiotics, is normally accomplished by the ingestion of the microorganisms in drinks, yoghurts, capsules, and other forms in such a way that the organism arrives in a viable condition in the large bowel. It has been demonstrated by Englyst H. N. et al (1987) "Polysaccharides breakdown by mixed populations of human faecal bacteria", FEMS Microbiology Ecol 95: 163-71, that the bacterial fermentation of resistant starch in the large bowel produces elevated levels of short chain fatty acids, particularly beneficial types such as propionate and butyrate.
The present inventors have realised that it would be desirable to not only deliver probiotic microorganisms to the large bowel but also to provide a medium that would function to promote the growth of the microorganisms when they reach the large bowel. Surprisingly, it has been found that modified or unmodified resistant starches may function both as a means to transport the probiotic microorganisms to the large bowel and as a growth medium for the microorganism delivered to the target region of the large bowel. International publication number WO 96/08261 discloses such probiotic compositions and the content of which is incorporated into this specification for the purposes of convenient cross-reference.
It would be advantageous to further increase the numbers and/or survival in the gastrointestinal tract of probiotic microoganisms provided to an animal or human so as to enhance the beneficial effect of these compositions. The present inventors have now developed improved probiotic compositions and methods of delivering probiotic microorganisms to the gastrointestinal tract of animals including humans.